Why are electric vehicle batteries swollen?

Electric vehicle battery bulge is one of the common faults of electric vehicle battery, which will directly affect the service life of electric vehicle battery. So, why are electric vehicle batteries bulging? The reasons are as follows. 1. The previous lead-acid batteries generally used the traditional cadmium-containing formula and applied external chemical conversion technology to produce. The cadmium-containing lead-acid batteries are resistant to high temperature and high current, but they have relatively large environmental pollution; and the current lead-acid batteries are strictly prohibited Containing cadmium, it is inevitable to charge the battery for a long time under high temperature and high current conditions.　　 2. In summer, the charger charges a 48V battery with a general voltage of 55V. In winter, the battery charge voltage is generally 61V, and the temperature can be controlled between -22°C and 55°C. If the charging voltage set by the charger exceeds this value, it means that the battery will be overcharged; overcharging will cause the battery to lose water until thermal runaway. Generally, bulging batteries are caused by overcharging, and the phenomenon of bulging in summer is much more serious than in winter! 　　 Three, inferior chargers will not turn the lights after fully charging the battery, and will not adjust the charging current according to the battery current, resulting in a large number of batteries Overcharge, the battery will charge up after multiple overcharges. 4. Generally, the battery should not be charged for more than 8 hours, and many people don’t care if they plug in the charger. They often charge overnight, and the charger and battery are in high temperature for a long time, which not only makes the charger easy to break, but also charges the battery. drum.　　 5. Frequent use of fast charging stations for charging leads to approximately 5% of the battery charge. The fast charging station uses a large current to charge for a period of time, which will cause serious gas loss and water loss of the battery. Long-term use is an important reason for the battery to blow up.　　6. u200bu200bMixing different types of chargers will also cause the battery to charge up. Different types of batteries have different chargers and cannot be used universally. However, some electric vehicle users often mix and use them during use. Use a 60V charger to charge a 48V battery, and a 20AH charger to charge a 12AH battery. , The charging voltage and current do not match, which will cause the battery to charge up.　　 Seven. Under normal circumstances, electric vehicle batteries will have a safety valve through which excessive pressure is released. However, there are individual batteries that cannot be released normally because the safety valve is not good, which causes the bulge to deform.　　 8. If the float charge voltage is set higher than the normal value, the temperature in the battery will rise rapidly, but the exhaust will not be timely. In this case, the battery will deform and bulge.　　9. Although the charger is of good quality, it may be bumped and shaken in the car for a long time, and the components may cause desoldering, resulting in poor contact, resulting in unstable current during charging and failure of the protection function, causing the battery to be charged.　　10. Batteries that have been exposed to high temperatures in summer or the temperature of the charging environment is too high, which will also cause deformation of the battery shell. According to the battery power, the charger can float for 2 hours after turning to the green light. When the ambient temperature is high, after riding, the surface temperature of the battery should be allowed to cool down before charging, avoiding charging in high temperature environments. Previous: What should I pay attention to when riding an electric bike on rainy days?